tenoning jig and a dado

[oohhmm]

I find all kinds of info on using either the jig or the dado. I'm wondering why not both?

I use a Grizzly tenoning jig to cut my tenons. I usually precut the shoulders and cheeks on the table saw then run them through the jig like everyone says to do. It works well but requires 8 passes for each tenon. I’m working on a piece that will require 48 tenons. That’s a lot of passes and a lot of room for mistakes. I’m wondering why it can’t be done with the jig and my dado. Using a face board to catch the excess blade of the dado, I can take off ¼ inch on each pass leaving an accurate shoulder/cheek on each pass.

I wrote Grizzly to ask why this shouldn’t be done, they replied that "the risk of kick back was too great” and it shouldn’t be done. If I’ve got my head correct on this, the orientation of blade to the wood (and grain) clamped into the jig is just a “vertical rip cut” and no different than a dado ripped horizontally into four faces of say, a 8/4 piece of stock? I would think the clamping action of the jig would provide even greater safety?

[AlanWS]

If you are asking about using the two outside cutters of your dado stack to cut tenons using your tenoning jig, it can be a great idea. A spacer between the two blades sets the tenon thickness, and both blades are raised through a ZCI. This setup allows you to cut perfect fitting tenons without readjusting for each cheek cut. But you still need to cut shoulders and sides separately.

If, on the other hand, you are asking about using a whole dado stack to cut tenons while the stock is clamped vertically into a tenoning jig, I think the main problem is that you don't get much for your effort. It will require a lot more power (you are reducing all of the waste to dust, rather than just the small amount required to sever the waste in a chunk) and the only cuts you avoid are the shoulder cuts. But these are needed to get clean shoulders.